Boxer (12)

'boxer' is the definition.
(I know that prizefighter is a type of boxer)
This is all the clue.
'boxer' is the definition.
(Muhammad Ali)
This is all the clue.
(Other definitions for ali that I've seen before include "Muhammad or Baba?" , "Late boxer" , "girl shortly" , "Fourth caliph of Islam" , "Son-in-law to Muhammad" .)